An analog-to-digital conversion (ADC) system generally receives an input analog signal and converts the signal to a digital coded value. ADC systems are largely integrated and replicated onto semiconductor wafers. The individual circuits are then cut into individual die, lead bonded and packaged for use in a final application. ADC systems may receive analog voltage and/or current signals representing various parameters from the real world (e.g., temperature, pressure, illumination), and may convert them to a digital form for consumption by a digital processor, such as a computer.
The conversion process may occur in stages, for example, sample-and-hold, quantize and encode. A sample-and-hold circuit samples the input analog signal and holds the sampled analog value in time. The sample-and-hold circuit may hold that sampled value, at least long enough for an encoder circuit to determine a unique digital code for the sampled input analog signal. The digital code may be assigned based on its correlation to one of a number of discrete quanta from a quantizer.
To improve the overall conversion speed of the ADC system, two or more ADCs may be employed in a time-interleaved fashion. In a time-interleaved ADC, each ADC block may convert a time slice portion of the overall signal.